1. Field of the Invention
This invention relates to a power supply circuitry, and more particularly, to an improved power supply circuitry.
2. Description of the Prior Art
Prior art power supply circuitry including a switching DC to DC up converter typically provide an output voltage of higher magnitude than an input voltage from a source voltage for a relatively narrow range of input voltage magnitudes. Such circuits will not operate in applications where a wide range of input voltage magnitudes must be accommodated. In addition, these circuits do not provide the capability of changing the magnitude of the output DC voltage in response to external inputs.
Prior art power supply circuitry which converts a battery voltage up to an output DC voltage of a greater magnitude generally do not maintain the output DC voltage over a wide range of input voltage magnitudes. For example, the output DC voltage of such circuits will tend to drop as the voltage source, such as a battery, becomes discharged or during voltage slumps due to peak current requirements.
For the foregoing and other shortcomings and problems, there has been a long felt need for an improved power supply circuitry.